XAML

When working in Expression Blend, the namespaces that are needed will be added automatically.

Load your project in Expression Blend and open the User Control that holds the RadChart. You have to use a dummy control in order to get the default style. To create one find the NoDataControl control in the 'Assets' pane and draw one on the art board. In the 'Objects and Timeline' pane select the NoDataControl, you've drawn and from the menu choose Object -> Edit Style -> Edit a Copy. You will be prompted for the name of the style and where to be placed.

If you choose to define the style in Application, it would be available for the entire application. This allows you to define a style only once and then reuse it where needed.

After clicking 'OK', Expression Blend will generate the default style of the NoDataControl control in the Resources section of your User Control. The properties available for the style will be loaded in the 'Properties' pane and you will be able to modify their default values. You can also edit the generated XAML in the XAML View or in Visual Studio.

To apply the style to the real control, set it to the NoDataControl property of the ChartArea.